镍离子对分光光度法测定水样中COD的影响

Effect of nickel ions on COD determination in water samples by spectrophotometry

通过测定Cr3+、Cr2O72-和Ni2+的吸收曲线及标准水样的COD,研究了Ni2+对分光光度法测定COD的影响。结果表明,当水样中Ni2+质量浓度<100mg/L时,对测定结果无明显影响;若水样中Ni2+质量浓度>100mg/L时,应将水样稀释后再进行测定。

The effect of nickel ions on COD determination by spectrophotometry has been studied based on the determination of absorption curves of Cr3＋、Cr2O72-and Ni2＋,and the COD of standard water samples.The results show that nickel ions have no effect on COD determination,if the concentration of nickel ions is less than 100 mg/L in the water sample.If the concentration of nickel ions is more than 100 mg/L,the COD of the water samples should be determined after the samples have been diluted.